The volar extension of the lunate facet of the distal radius: a quantitative anatomic study
Related Experiment Video
Updated: Aug 7, 2026

Vascularized Composite Hand Allograft Procurement and Preparation for Distal and Proximal Forearm Allotransplantation: A Stepwise Approach
Published on: May 23, 2025
Jonas Andermahr1, Santiago Lozano-Calderon, Ted Trafton
1Clinic of Trauma, Hand, and Reconstructive Surgery, University of Cologne, Köln, Germany.
Purpose:
To describe quantitatively the protrusion of the volar part of the lunate facet of the distal radius articular surface anterior to the volar metaphyseal cortex, which is susceptible to fracture and can be difficult to control with plates and screws alone.
Methods:
Quantitative anatomic measurements of 48 3-dimensional computed tomography scans of the distal radius were analyzed to quantify the anatomy of the volar part of the lunate facet of the distal radius. The measurements were scaled to account for overall bone size. Male and female anatomies were compared.
Results:
The height and width of the volar extension of the lunate facet were 3 +/- 1 mm and 19 +/- 4 mm, respectively. The mean height of the lunate facet was 19 +/- 3 mm. An average of 16% of the lunate facet projects anterior to the flat volar surface of the distal radius. The thickness of the volar extension of the lunate facet averaged 5 +/- 1 mm. There were no statistically significant differences between men and women for any of the scaled measurements.
Conclusions:
The observation that the volar lunate facet projects approximately 3 mm (or 16% of the dorsal-volar height of the lunate facet) anterior to the flat volar surface of the distal radius and is approximately 5 mm thick helps explain its relative vulnerability to injury and the difficulty encountered when trying to secure it with a plate and screws.
Related Concept Videos
Bones of the Upper Limb: Radius
The radius has a nail-shaped head, and a short...
Bones of the Upper Limb: Ulna
Muscles that Move the Forearm
Forearm Flexors
The biceps brachii, brachialis, and brachioradialis are forearm flexors. The biceps brachii is made up of two heads. Its long head originates at the supraglenoid tubercle of the scapula, whereas that of the short head is...
Muscles of the Forearm that Move the Hand and Fingers
Anterior Compartment
The anterior compartment muscles originate from the humerus. They primarily function as flexors and are also known as flexor muscles. They typically insert on the carpals, metacarpals, and phalanges. The superficial layer includes the flexor carpi radialis,...
Bones of the Upper Limb: Humerus